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This paper aims to present a new wireless power transfer technique using capacitive coupling. The capacitive power transfer (CPT) system has been introduced as an attractive alternative to the traditional inductive coupling method. The CPT offers benefits such as simple topology, fewer components, better electromagnetic interference (EMI) performance and robustness to surrounding metallic elements.

A class-E inverter together with and without inductor capacitor (LC) matching circuit has been utilised in this work because of its ability to perform the DC-to-AC inversion efficiently with significant reduction in switching losses. The validity of the proposed concept has been verified by conducting a laboratory experiment of the CPT system.

The performances for both systems are analysed and evaluated. A 9.7 W output power is generated through a combined interface [printed circuit board (PCB) plate] capacitance of 2.82 nF at an operating frequency of 1 MHz, with 97 per cent efficiency for 0.25 mm coupling gap distance.

An efficient CPT system with class-E LC matching topology is proposed in this paper. With this topology, the zero-voltage switching can be achieved even if the load is different by properly designing the LC matching transformation circuit.

This paper aims to present an analysis of a hybrid high‐voltage switch based on the parallel connection of IGBT and IGCT. The proposed configuration combines the advantages of both semiconductors, resulting in substantially reduced power losses. Such energy efficient switches could be used in high‐power systems where the requirements of high switching frequency or decreased cooling systems are a major concern.

The operation principle of the switch is described and simulated. The power dissipation is estimated at different operation conditions. Further, the implementation possibilities of the proposed switch configuration in a three‐level NPC inverter are analysed. The operation with the proposed PWM control algorithm is simulated and inverter power loss distribution is estimated.

According to estimations, the proposed hybrid switch configuration allows the reduction of total losses in semiconductors by at least 50 percent. If two of these switches are used in a three‐level NPC inverter as outer switches, the total losses of the inverter are reduced by 27 percent, at the same time the losses in the most stressed semiconductor device are reduced by a factor of 2.25. Therefore, achieving higher power density is possible.

The proposed switch configuration is intended for high‐power (>500 KVA) industrial, marine and railway traction systems, such as FACTS and high power variable frequency AC drives.

The paper presents the novel energy‐efficient high‐voltage switch based on the parallel connection of commercially available IGBTs and IGCTs.

When wearable and implantable devices first arose in the 1970s, they were rigid and clashed dramatically with our soft, pliable skin and organs. The past two decades have witnessed a major upheaval in these devices. Traditional electronics are six orders of magnitude stiffer than soft tissue. As a result, when rigid electronics are integrated with the human body, severe challenges in both mechanical and geometrical form mismatch occur. This mismatch creates an uneven contact at the interface of soft-tissue, leading to noisy and unreliable data gathering of the body’s vital signs. This paper aims to predict the role that discreet, seamless medical devices will play in personalized health care by discussing novel solutions for alleviating this interface mismatch and exploring the challenges in developing and commercializing such devices.

Since the form factors of biology cannot be changed to match those of rigid devices, conformable devices that mimic the shape and mechanical properties of soft body tissue must be designed and fabricated. These conformable devices play the role of imperceptible medical interfaces. Such interfaces can help scientists and medical practitioners to gain further insights into the body by providing an accurate and reliable instrument that can conform closely to the target areas of interest for continuous, long-term monitoring of the human body, while improving user experience.

The authors have highlighted current attempts of mechanically adaptive devices for health care, and the authors forecast key aspects for the future of these conformable biomedical devices and the ways in which these devices will revolutionize how health care is administered or obtained.

The authors conclude this paper with the perspective on the challenges of implementing this technology for practical use, including device packaging, environmental life cycle, data privacy, industry partnership and collaboration.

Wind‐diesel sets offered as a reliable hybrid isolated power systems with reduction of fuel consumption, consists of variable speed wind turbines and fixed speed diesel engines. Load and wind energy variations cause, that the load power of the diesel genset is varied in wide range. Fixed speed generation set operates with the best efficiency only in a narrow range of the load, therefore implementation of a load adaptive, adjustable speed genset may additionally reduce fuel consumption.

Analysis of the system components model, simulation and laboratory tests on a small‐scale model.

Topology and output voltage control method of four‐wire adjustable speed autonomous wind‐diesel system dedicated for isolated power plants with high wind penetration.

The paper presents only part of the work which has to be done for the complete system. Load and energy management has to be applied in standalone system, as not in each operating point of proposed wind‐diesel system, can rated load be supplied. To fully prove the proposed system and control concept, tests of megawatt range system are advisable. To evaluate the fuel saving, a real wind and load profile in a selected isolated place is needed.

Every adjustable speed generation systems can save fuel. However, proposed topology in main part consists of known and implemented solutions, therefore costs of the new installation will not be increased significantly.

Proposed costs effective topology of adjustable speed wind‐diesel generation system has not been presented by any other authors. Standalone operation of doubly fed induction generator system is rarely reported in the papers.

Proposes the application of novel control strategy in power transistors (insulated gate bipolar transistors – IGBT) based on AC/DC/AC converter with active filtering function. Seeks to investigate the possibilities of operating drive system under distorted line voltage with unity power factor and reduced dc‐link capacitor.

A novel control strategy is proposed based on direct power and direct torque control with space vectors modulators scheme which seems to be most promising. This method is investigated, implemented and examined in the laboratory setup. Different working conditions are taken into consideration.

Provides information how the proposed system works under motoring and regenerating modes. Good behaviors of the system in steady state in transience are shown. Very good stabilization of the dc‐link voltage under transient is achieved. Almost sinusoidal line current is obtained. Very good compensation of nonlinear load is also achieved.

This is not an exhaustive investigation. The system should be tested with different input inductances (or LCL filters) and with reduced dc‐link capacitor. Moreover, laboratory tests with higher power should be performed in the future.

A useful source of information and an example of how a fully controlled AC/DC/AC converter with active filtering function works. It could be an important basis for a prototype for industry.

Although the direct power control with space vector modulator (DPC‐SVM) and direct torque control with space vector modulator (DTC‐SVM) schemes have been described in the literature separately, it is analyzed for the first time and investigated together for control of the AC/DC/AC converter. Additionally, active filtering provides a feature of power compensation. It could be the basis for a clean power system design.

To improve the voltage quality in AC adjustable high-power-speed-drive applications, the purpose of the paper is to provide a large number of output levels without increasing the number of commutation cells in the three-phase, n-cells flying capacitor voltage source asymmetric Multilevel Inverter (MI). The concept is based on the selection of different ratios between the breakdown voltages of two successive power devices. The new mathematical model is developed under various ratios, allows a thorough investigation of the harmonic distortions, flying capacitor energy storage, flying capacitor voltage balancing controllability and blocking voltage insulated gate bipolar transistor (IGBT) capability.

The asymmetrical design provides a large number of output levels without increasing the number of commutation cells. The important new analytical expression of capacitors voltage distribution is derived and extended to any ratio between the switch breakdown voltages of two successive power devices.

The detailed simulation study of the proposed concept has been carried out using MATLAB/Simulink. The power switches control of the three-phase three-cell MI is assured by new phase-shifted-multi-carrier pulse width modulation. The space vector representation is used to show the regular and irregular step output voltage in the complex plan (α,β).

In the paper, the n cells flying capacitor inverter, which typically operates in the (n + 1) levels mode, was extended to (n + 2), (n + 3) … until 2ⁿ levels with regular or irregular step output voltage. Consequently, the claimed advantages of the asymmetric MI are to improve power quality by reducing harmonic distortions and to reduce the requirement on capacitive energy storage in the circuit.

The limited energy density of batteries generates the need for high-performance power sources for emerging eVTOL applications with radical operational improvement potential over traditional aircraft. This paper aims to evaluate on-design and off-design recuperated turbogenerator performances based on newly developed compression loaded ceramic turbines, the Inside-out Ceramic Turbine (ICT), in order to select the optimum engine configuration for sub-megawatt systems.

System-level thermal engine modeling is combined with electric generators and power electronics performance predictions to obtain the Pareto front between efficiency and power density for a variety of engine designs, both for recuperated and simple cycle turbines. Part load efficiency for those engines are evaluated, and the results are used for an engine selection based on a simplified eVTOL mission capability.

By operating with high turbine inlet temperature, variable output speed and adequately sized recuperator, a turbogenerator provides exceptional efficiency at both nominal power and part load operation for a turbomachine, while maintaining the high power density required for aircraft. In application with a high peak-to-cruise power ratio, such power source would provide eight times the range of battery-electric power pack and an 80% improvement over the state-of-the-art simple cycle turbogenerator.

The implementation of a recuperator would provide additional gains especially important for military and on-demand mobility applications, notably reducing the heat signature and noise of the system. The engine low-pressure ratio reduces its complexity and combined with the fuel savings, the system could significantly reduce operational cost.

Implementation of radically new ICT architecture provides the key element to make a sub-megawatt recuperated turbogenerator viable in terms of power density. The synergetic combination of a recuperator, high temperature turbine and variable speed electric generator provides drastic improvement over simple-cycle turbines, making such a system highly relevant as the power source for future eVTOL applications.